How can we use foxes and rabbits help transmit secret messages? No animal cruelty is necessary - a new technique encodes messages using a predator-prey model normally used to predict the changes in animal populations. This advance in steganography could revolutionize the art of secrecy.

Moscow communicated with alleged spies in America by encoding instructions on public websites. It's a process called steganography. And it's one of a slew of high-tech and time-tested methods that the deep-cover agents and their Russian handlers used to pass information